The pipe in the center carries toxic waste gas and waste liquid that is pumped and burned at the top of the pipe. 

When it deals with homeowners you really have to explain why they should go with you rather than just looking, crunching numbers and making offers, they could have gotten burned etc by somebody eIse, taught several people to ask what I am about to say and boy did it work.

Currently my burn rate for this property $5,000/month before utilities for my spaces! 

The CO would be gases that are unwanted mostly. basically every heating appliance that "burns" gas will cause CO.

Then again, California almost burned down in 2018, partly thanks to the low humidity. 

having lived most of my life in the North Bay of CA we have seen devastating fires that burnt down thousands of homes.. these hills burn about every 30 to 50 years.. its the folks moving into what was rural areas that creates these issues.. but then think the Oakland fire 30 years ago 4500 homes burnt down there .. now you would never even really know it if you did not know what existed prior.

I guess as long as I add that cost into an expense for flip, it can alleviate unwanted headaches even if nothing were ever to happen.

It's fun to look at people with a couple of mil to burn. :)Seriously though, I am trying to figure out your motives.

Meaning even if the bedrooms didn’t burn, you still have to take out the drywall seal the studs, joist, rafters, and subfloor for smoke smell.  You will need all new insulation, most likely a rewire, and new HVAC system.  Not to mention any structural damage where there was a physical fire.

sounds like that Is worse than a boarded up or burned out house as a neighbor .